Deckle

A frictionless, spaced-repetition flashcard app. Everything runs client-side — no backend, no account, no server-side database. Your data lives in your browser's IndexedDB and never leaves it unless you export it yourself.

Features

• Projects → Decks → Cards — a flat, simple hierarchy (no nesting, no tags)
• FSRS scheduling — modern spaced-repetition algorithm (the same one Anki now defaults to), not the older SM-2
• Basic and Cloze cards, with image/audio embeds and a live markdown preview while you write
• Review session built for both desktop and mobile: keyboard shortcuts (Space to reveal, 1-4 to grade) and swipe gestures, with next-interval previews on every grade button
• Dashboard showing what's due today, broken down by project
• Stats — retention rate, review streak, 7-day due forecast
• Reminders — a daily time + minimum-due threshold, surfaced as a browser notification when the installed app is open
• Passphrase lock screen (a UI gate, not encryption — see below)
• Dark/light theme, defaulting to system preference, overridable anytime
• Manual JSON backup (export/import), with a nudge if it's been a while
• Installable PWA — works offline once loaded, add-to-home-screen on mobile and desktop

Known limitations (by design, for now)

• No sync between devices/browsers — the manual JSON export/import is the only way to move data around
• The passphrase lock is a UI gate only; data is not encrypted at rest
• No AI-assisted card generation (e.g. from a photo) — everything is typed or pasted in by hand

Tech stack

Layer	Choice
Framework	Angular (standalone components, Signals, zoneless change detection)
Scheduling	ts-fsrs
Storage	Dexie over IndexedDB
Styling	Tailwind CSS v4
UI components	spartan-ng — headless components on Angular CDK
Markdown	marked, rendered through Angular's built-in sanitizer
Hosting	GitHub Pages, deployed via GitHub Actions

Project structure

src/app/
  core/
    data/       Dexie database definition
    models/     Project, Deck, Card, ReviewLogEntry, MediaAsset, AppSettings
    services/   FSRS, project/deck/card CRUD, review, settings, theme, lock,
                backup, notifications, media, markdown rendering
    utils/      cloze parsing, interval formatting, id generation
  features/     one folder per screen (dashboard, projects, decks, cards,
                review, stats, settings, lock)
  shared/       app shell (nav), reusable components (theme toggle, card
                preview)
libs/ui/        generated spartan-ng components (button, dialog, card, …)

Development

Requires Node 22 (see .nvmrc).

npm install
ng serve

Open http://localhost:4200/.

ng build   # production build to dist/deckle
ng test    # unit tests (Vitest)

Deployment

Pushing to main triggers .github/workflows/deploy.yml, which builds the app with --base-href /<repo-name>/ and publishes it to GitHub Pages via GitHub Actions.

Before the first deploy:

1. The repo must be public (GitHub Pages needs a paid plan to publish from a private repo).
2. In the repo's Settings → Pages, set Build and deployment → Source to GitHub Actions.